A method and apparatus to determine possible atrial fibrillation or
absence of atrial fibrillation that includes detecting pulse rhythms from
a succession of time intervals each corresponding to a respective
interval of time between successive pulse beats; analyzing the detected
pulse rhythms to make a determination of possible atrial fibrillation;
indicating the possible atrial fibrillation from the determination; or
making a determination of the absence of atrial fibrillation.